ColorAcademy 2005

British Standards Institution

The British Standards Institution's range of Paint Colours BS4800:1972 is a selection from the Framework for Colour Co-ordination for Building Purposes BS 5252:1976 designed to promote order and economy. The Framework incorporates a number of special features which make it an improvement on previous BS systems, and many other ranges are being derived from it, vitreous enamels, flooring, plastics and so on.

Specification

HUE
In the folding chart of the Framework, the twelve hues are placed in twelve horizontal rows, each row being of a different hue. The top row is red-purple 02, flowed by red 04, yellow-red (orange*) 06, yellow-red (yellowish-orange*) 08, yellow 10, green-yellow (lime*) 12, green 14, blue-green (turquoise*) 16, blue 18, purple-blue 20, violet 22, and purple 24 on the lowest hue row.

GREYNESS
The hue rows range across sample groups A and B, subdued colours, and C and D more pronounced colours, ascending to the fullest power in the E group. The five groups A,B,C,D and E are steps in a grey-to-clear sequence. This differs from the Munsell system in that a special consideration of greyness rather than chroma makes it possible to construct more consistent scales of samples optically equivalent in key* where equivalent Munsell value-and-chroma is unable to achieve this. Greyness is indexed from maximum greyness to zero-greyness. It is the negative correlate where clearness and pronouncedness of hue is the positive factor.

Neutral greys are in a separate row 00 at the foot of A group. Clear white and black are at the foot of the zero-greyness group E.

WEIGHT
The greyness groups A,B,C,D and E have columns of colours ranging in each group from lightest on the left of the group to darkest on the right. This light-to-dark gradation within each group is called 'weight' and varies from light to heavy. For identification the columns are numbered across the whole framework from 01 at the extreme left of A group to 58 at the extreme right of E group. The samples in any one column are adjusted to appear the same key*. This is called 'equal weight'.

Munsell references

The BS Framework gives approximate Munsell references for additional information. Though no one system has universal currency amongst artists and designers, the Munsell system has been used widely in the building industry. It helps relate old BSs to new; and the 'value' figure is easily converted into percentage reflectance in lighting design calculations. Munsell terms such as value and chroma (which means intensity or saturation as against greyness) have been adopted both in general theory in the description of the BS adjustments to Munsell, and also with specific reference to Munsell notations.

A stimulus gradient*

The colour stimulus gradient* as described in 'Working with the Methuen Handbook' (Journal of the Colour Group no. 14) introduced a new way of thinking about colour as far as the modern technology of colour is concerned. The BS Framework now presents the first systematic attempt to base colour ranges on that most important consideration of the designer, the level at which he wants to pitch visual impact.* At that level the Framework provides a number of constant colour effects, such as equivalence of key* from one hue to another (much more consistent than Munsell) and equivalence of hue from one level of pronouncedness to another, so that the groups A,B,C,D and E form a chromatic stimulus gradient* ranging from neutrals and subdued colours to those giving rise to peak hue discrimination.

*Terms not used in the BSI explanation of their ranges.

For further information, please visit the BSI: here (this open the BSI website in a new browser window)

Bibliography

KORNERUP, A, WANSCHER, J.H (1978) Methuen Handbook of Colour. London Eyre Methuen.